Multicolor cinematograph and other film



May 13, 1930. J, E, THORNTON 1,758,768

HULTICOLOR CINEMATOGRAPH AND OTHER FILM Filed May 5, 1924 WlorzzPatented May 13, 1930 UNETED STATES PATENT OFFICE JOHN EDWARD THORNTON,OF LONDON, ENGLAND, ASSIGNOR TO JOHN OWDEN OBRIEN, F MANCHESTER, ENGLANDMULTICOLOR CIN EMATOGRAPH AND OTHER FILM Application led May 5, 192,Serial No. 711,254, and in Great Britain May 18, 1923.

This invention relates to the manufacture and production of double widthmulti-color cinematograph film-positives either in four or three colors,of the screen-filter type, as

` described in my co-pending application, Serial No. 711,251, filed May5, 1924, upon one half of which double width film is formed a half-imageor section-picture in two colors and upon the other half anotherhalf-image in two other colors, both half-pictures being complementarytoeach other, and both halfpictures being necessary to produce acomplete or full picture.

ccording to this invention, I make a positive film in which the imagesare produced on a silver bromide panchromatic emulsion by printing froma negative through the celluloid support and the two two-color screensinterposed between the celluloid and the emulsion, the lm being ofdouble standard width adapted to receive partial images in two colorsupon both half widths or strips. I

To more clearly illustrate the invention, attention is invited to theaccompanying drawings, in which igure 1 is a plan view of a double widthfilm sensitized with a silver bromide emulsion.

Figure 2 is a transverse section greatl enlarged in depth through adouble widt Hlm material, the picture being printed through the colorscreen and the celluloid base as shown by the arrow.

Figures 3, 4, 5V and 6 are plan views greatly enlarged of portions ofthe color screens adjacent to the center line of the double width Figure7 is a plan view of a double width film showino' a pair of images formedone upon each alf, the images having been printed through theirrespective color screens.

Referring to the drawings, the celluloid support which. is made in dou-45 ble width of single thickness and is, therefore, as will presentlyappear, made to form the two strips a-a. Upon this support is placed anadhesive substratum B, the layer C of the two-color filter screens toeach strip 50 a-a with the final panchromatic emulsion A designates Dbeing placed and adhesively attached to the support through the mediumof the substratum.

This is accomplished in the following manner, v1z:- 55

Structure of the negative /hn stratum B and superimposed upon thesubstratum two filter-screens C are formed sideby-side, one of' whichfilters two colors of the subject photographed and the other screen theremaining two colors. Superimposed upon these two screens is a layer ofrapid panchromatie emulsion D, the pictures being photographed thereonby exposing thc film in the camera with the celluloid at the front, sothat light passes first through the celluloid, then through the twofilters, and thence to the sensitive layer, upon which two componentimages are thus formed side by side7 both images being differentlyltered, but forming a complementary pair capable of producing printswhich give a complete color-reconstruction of the original subject.

The screens of the negative consist of a mosaic of fine lines, dots orgrains of color, 'l two colors being alternately interspersed on onehalf the film and two different colors interspersed on the other halfandin the manner as shown in Figs. 3, 4 and 5.

For four-color pictures there are four such colors in the pair ofscreens, but for three color pictures there are only three colors, oneof the colors being repeated in both screens so that there are still twocolors in each screen. f"

` pictures as in the negative Structure of the positive jbm,

The film-material for the positive pictures is identical with thenegative-material above described, but with the difference that it isonly half standard thickness. The screens are made for each four-coloror three-color film, and composed of a mosaic of fine lines, dots orgrains of color, two colors being alternately interspersed on one halfthe film and two different colors interspersed on the other half.

In the present invention each pair of differential positive images isprinted as black silver images of a negative character in one layer ofnon-colored sensitive silver-brom'id emulsion superimposed upon a screenof colored lines, dots, or other pattern which are visible bytransmitted light only to the extent allowed by the silver image, whichforms a mask or cut-out for portions of the colorscreens andallows lightto pass through the remainder and thus constitute the positive picture.

The positive process used in this invention is therefore quite differentfrom the processes used in any of the other applications in which theimages themselves are colored images of a positive character.

For a four-color print the color-screens `will be a complementary pairsuch as crimson red and blue green upon one half of the film, andanother complementary pair such as blueviolet and orange-yellow upon theotherhalf. In this way a quadrate of color is completed.

For a three-color print the color-screens upon each half will be onlysemi-complementary in their coloring, because, as shown in Fig. 6, thefirst color such as red will be upon one half, the second color such asblue upon the other half, and the third color such as orange-ygllow willbe repeated upon both halves, bing interspersed with the colors alreadythere. In this way the trial of color is completed.

f Printing the color positives vThe doublewidth positive material ispreferably exposed and printed by projection, either through one largelens which covers the fullwidth of strip and projects both images, orthrough two lenses which each cover only half the strip, each lens projectig each image separately, which permits of adjustment of accuracy of'registration.

Modifications A number of modifications are possible within the scope ofthe invention without departing from the principles described. Forexample The two negatives may be formed upon two separate single-widthfilms, and the two posiany deviaton from strict tives may also beprinted upon two separate single-width films.

Four-color and and film-positives may be made of the various rectangularforms for ordinary amateur and professional photography. This systemgives not only a simpler method of producing color positives but also abetter result than most of the color-photograph systems now in use. A

What I claim as my invention and desire to protect by Letters Patentis 1. A double width multi-color screen-mosaic picture positivevcomprising a double width film of transparent material, a colormosaicscreen in two colors covering each half width of the double width film,.an adhesive substratum between each color-screen and each half width ofthe film, and a half-picture of negative character upon each half widthof the film superimposed on its own color-screen.

2. A double width multi-color screen film picture positive comprising adouble-width film of transparent waterproof material, an adhesivesubstratum covering both halves of said film, a tw-o-color mosaicforming a color screen or light filter entirely covering one half of thedouble width film and indissolubly attached thereto by the adhesivesubstratum, a second ,two-color mosaic forming a color screen or lightfilter entirely covering the other half of the double width film andindissolubly attached thereto by the adhesive substratum, the two colorsof one filter being different from but complementary to those of theother filter, and two half pictures of negative character, one upon eachhalf of the film, each imposed upon its own color screen, the finalpositive image being actually formed by combination of such portions ofthe two screens or filters as remain uncovered by the two black silverimages of negative character.

3. A. double width multi-color screen-film positive as in claim l;produced with four colors in two images, crimson-red and bluegreen onone half of the double width film and blue-violet and orange-yellow onthe other half of the double width film.

In testimony whereof I have hereunto set my hand.

JOHN EDWARD THORNTON.

three-color film-negatives

